The Social Vulnerability Index
What is social vulnerability?
Every community must prepare for and respond to hazardous events, whether a natural disaster like a tornado or a disease outbreak, or an anthropogenic event such as a harmful chemical spill. The degree to which a community exhibits certain social conditions, including high poverty, low percentage of vehicle access, or crowded households, may affect that community’s ability to prevent human suffering and financial loss in the event of disaster. These factors describe a community’s social vulnerability.
How can SVI help communities be better prepared for hazardous events?
SVI provides specific socially and spatially relevant information to help public health officials and local planners better prepare communities to respond to emergency events such as severe weather, floods, disease outbreaks, or chemical exposure.
SVI can be used to:
- Assess community need during emergency preparedness planning.
- Estimate the type and amount of needed supplies such as food, water, medicine, and bedding.
- Decide how many emergency personnel are required to assist people.
- Identify areas in need of emergency shelters.
- Create a plan to evacuate people, accounting for those who have special needs, such as those without vehicles, the elderly, or people who do not speak English well.
- Identify communities that will need continued support to recover following an emergency or natural disaster.
What is measured?
The most recent SVI data come from the 2016-2020 American Community Survey and include the following four themes and theme-specific measures (total of 16).
Each geography is percentile-ranked on every measure, with a higher percentile-rank indicating greater vulnerability. Percentile-ranks are then summed for each theme to generate the theme-specific rank. Similarly, the four themes are summed to generate an overall percentile-rank.
In our case, our interest lies in Ohio and hence we will focus strictly on Ohio’s counties and tracts, cycling through each theme and then the overall SVI as well.
Ohio’s Counties
Given what we know about Appalachian Ohio, it would be no surprise if overall and for most of the themes we saw more Appalachian counties ranking very high in vulnerability. One way to see this spatially would be via maps, and then also by way of looking at where most counties fall in the rank of 1 through 88.
Overall, Clermont county is the least vulnerable Appalachian county, ranking 69th overall, with the remaining less vulnerable counties all being non-Appalachian counties. At the other end of the distribution, 12 of the 20 most vulnerable counties are Appalachian. A similar pattern is evident within some of the themes – 14 of the 20 most vulnerable counties in the socioeconomic domain are Appalachian, and so are 11 of the 20 most vulnerable counties in the housing type and transportation domain. In household characteristics, and racial/ethnic minority status, more non-Appalachian than Appalachian counties fall within the set of the 20 most vulnerable counties.
The maps are shown below, first for the overall SVI rank, and then for each theme.
The Tracts
